Bio

Clinical Focus


  • Vascular Surgical Procedures
  • Superior Mesenteric Artery Syndrome
  • Angioplasty, Percutaneous Transluminal
  • Endovascular aneurysm repair
  • Thoracoabdominal Aortic Aneurysm
  • Vascular Surgery
  • Mesenteric Vascular Occlusion
  • Carotid Stenosis
  • Renal artery stenosis
  • Varicose Veins
  • Complex aortic surgery
  • Thoracic Aortic Aneurysm
  • Intermittent Claudication
  • Carotid Artery Stenting
  • Abdominal Aortic Aneurysm
  • Peripheral Arterial Disease

Academic Appointments


Administrative Appointments


  • Co-chair, Clinic Advisory Council, SHC (2010 - Present)
  • Director, Stanford Vascular Laboratory, Stanford Hospital and Clinics (2010 - Present)
  • Member, Patient Experience Steering Committee, Stanford Hospital and Clinics (2010 - Present)
  • Director, Vascular Surgery Clinics, Stanford Hospital and Clinics (2010 - Present)

Professional Education


  • Fellowship:University of Wisconsin (06/2006) WI
  • Residency:Stanford Hospital and Clinics - Dept of Surgery (09/1992) CA
  • Medical Education:Harvard Medical School (06/1987) MA
  • Board Certification: Vascular Surgery, American Board of Surgery (2007)
  • Board Certification: General Surgery, American Board of Surgery (1994)
  • M.D., Harvard University, Medicine (1987)
  • Residency, Stanford University, General Surgery (1992)
  • Fellowship, Stanford University, Transplant Surgery (1993)
  • Fellowship, University of Wisconsin, Vascular Surgery (2006)
  • Board Certification, Vascular Surgery, American Board of Surgery (2007)
  • Board Certification, General Surgery, American Board of Surgery (1994)

Research & Scholarship

Current Research and Scholarly Interests


Dr. Mell's research interest focus on comparative effectiveness of health care delivery for complex surgical diseases, including optimizing outcomes and cost effectiveness.

Dr. Mell's clinical interests include all aspects of vascular surgery, with a special emphasis on surgery for complex aortic disease, including endovascular repair of abdominal aortic aneurysm.

Clinical Trials


  • Zenith(R) Low Profile AAA Endovascular Graft Clinical Study Recruiting

    The Zenith(R) Low Profile AAA Endovascular Graft Clinical Study is a clinical trial approved by US FDA to study the safety and effectiveness of the Zenith(R) Low Profile AAA Endovascular Graft in the treatment of abdominal aortic, aorto-iliac, and iliac aneurysms.

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  • Endurant Bifurcated and Aorto-Uni-Iliac (AUI) Stent Graft System Not Recruiting

    To demonstrate safety and effectiveness of the Endurant Stent Graft in the treatment of Abdominal Aortic or Aorto-Uni-Iliac Aneurysms.

    Stanford is currently not accepting patients for this trial. For more information, please contact Jason Lee, (650) 725 - 5227.

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  • CHOICE: Carotid Stenting For High Surgical-Risk Patients Not Recruiting

    The purposes of this study is to 1) Provide additional information that the commercially available Abbott Vascular Carotid Stent Systems and Embolic Protection Systems can be used successfully by a wide range of physicians under commercial use conditions. 2) Provide an ongoing post-market surveillance mechanism for documentation of clinical outcomes and for possible extension of the Centers for Medicare and Medicaid Services (CMS) coverage to a broader group of patients.

    Stanford is currently not accepting patients for this trial. For more information, please contact Ronald Dalman, (650) 725 - 5227.

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  • Endurant Stent Graft System Post Approval Study Not Recruiting

    The purpose of the study is to demonstrate the long term safety and effectiveness of the Endurant Stent Graft System for the endovascular treatment of infrarenal abdominal aortic aneurysms in a post-approval environment, through the endpoints established in this protocol. The clinical objective of the study is to evaluate the long term safety and effectiveness of the Endurant Stent Graft System assessed at 5 years through freedom from Aneurysm-Related Mortality (ARM).

    Stanford is currently not accepting patients for this trial. For more information, please contact Ronald Dalman, (650) 725 - 5227.

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  • PRESERVE-Zenith® Iliac Branch Clinical Study Recruiting

    The PRESERVE-Zenith® Iliac Branch Clinical Study is a clinical trial to study the safety and effectiveness of the Zenith® Branch Endovascular Graft-Iliac Bifurcation in combination with the Zenith® Connection Endovascular Stent/ConnectSX™/Atrium iCAST™ covered stent in the treatment of aorto-iliac and iliac aneurysms.

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Teaching

2013-14 Courses


Publications

Journal Articles


  • Gaps in preoperative surveillance and rupture of abdominal aortic aneurysms among Medicare beneficiaries. Journal of vascular surgery Mell, M. W., Baker, L. C., Dalman, R. L., Hlatky, M. A. 2014; 59 (3): 583-588

    Abstract

    Screening and surveillance are recommended in the management of small abdominal aortic aneurysms (AAAs). Gaps in surveillance after early diagnosis may lead to unrecognized AAA growth, rupture, and death. This study investigates the frequency and predictors of rupture of previously diagnosed AAAs.Data were extracted from Medicare claims for patients who underwent AAA repair between 2006 and 2009. Relevant preoperative abdominal imaging exams were tabulated up to 5 years prior to AAA repair. Repair for ruptured AAAs was compared with repair for intact AAAs for those with an early diagnosis of an AAA, defined as having received imaging at least 6 months prior to surgery. Gaps in surveillance were defined as no image within 1 year of surgery or no imaging for more than a 2-year time span after the initial image. Logistic regression was used to examine independent predictors of rupture despite early diagnosis.A total of 9298 patients had repair after early diagnosis, with rupture occurring in 441 (4.7%). Those with ruptured AAAs were older (80.2 ± 6.9 vs 77.6 ± 6.2 years; P < .001), received fewer images prior to repair (5.7 ± 4.1 vs 6.5 ± 3.5; P = .001), were less likely to be treated in a high-volume hospital (45.4% vs 59.5%; P < .001), and were more likely to have had gaps in surveillance (47.4% vs 11.8%; P < .001) compared with those receiving repair for intact AAAs. After adjusting for medical comorbidities, gaps in surveillance remained the largest predictor of rupture in a multivariate analysis (odds ratio, 5.82; 95% confidence interval, 4.64-7.31; P < .001).Despite previous diagnosis of AAA, many patients experience rupture prior to repair. Improved mechanisms for surveillance are needed to prevent rupture and ensure timely repair for patients with AAAs.

    View details for DOI 10.1016/j.jvs.2013.09.032

    View details for PubMedID 24246537

  • Modern advances in vascular trauma. Surgical clinics of North America Callcut, R. A., Mell, M. W. 2013; 93 (4): 941-961

    Abstract

    Early diagnosis and intervention are paramount for improving the likelihood of a favorable outcome for traumatic vascular injuries. As technology has rapidly diversified, the diagnostic and therapeutic approaches available for vascular injuries have evolved. Mortality and morbidity from vascular injury have declined over the last decade. The use of vascular shunts and tourniquets has become standard of care in military medicine.

    View details for DOI 10.1016/j.suc.2013.04.010

    View details for PubMedID 23885939

  • No increased mortality with early aortic aneurysm disease JOURNAL OF VASCULAR SURGERY Mell, M., White, J. J., Hill, B. B., Hastie, T., Dalman, R. L. 2012; 56 (5): 1246-1251

    Abstract

    In addition to increased risks for aneurysm-related death, previous studies have determined that all-cause mortality in abdominal aortic aneurysm (AAA) patients is excessive and equivalent to that associated with coronary heart disease. These studies largely preceded the current era of coronary heart disease risk factor management, however, and no recent study has examined contemporary mortality associated with early AAA disease (aneurysm diameter between 3 and 5 cm). As part of an ongoing natural history study of AAA, we report the mortality risk associated with presence of early disease.Participants were recruited from three distinct health care systems in Northern California between 2006 and 2011. Aneurysm diameter, demographic information, comorbidities, medication history, and plasma for biomarker analysis were collected at study entry. Survival status was determined at follow-up. Data were analyzed with t-tests or ?(2) tests where appropriate. Freedom from death was calculated via Cox proportional hazards modeling; the relevance of individual predictors on mortality was determined by log-rank test.The study enrolled 634 AAA patients; age 76.4 ± 8.0 years, aortic diameter 3.86 ± 0.7 cm. Participants were mostly male (88.8%), not current smokers (81.6%), and taking statins (76.7%). Mean follow-up was 2.1 ± 1.0 years. Estimated 1- and 3-year survival was 98.2% and 90.9%, respectively. Factors independently associated with mortality included larger aneurysm size (hazard ratio, 2.12; 95% confidence interval, 1.26-3.57 for diameter >4.0 cm) and diabetes (hazard ratio, 2.24; 95% confidence interval, 1.12-4.47). After adjusting for patient-level factors, health care system independently predicted mortality.Contemporary all-cause mortality for patients with early AAA disease is lower than that previously reported. Further research is warranted to determine important factors that contribute to improved survival in early AAA disease.

    View details for DOI 10.1016/j.jvs.2012.04.023

    View details for Web of Science ID 000310428200007

    View details for PubMedID 22832264

  • Impact of the Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act on Abdominal Ultrasonography Use Among Medicare Beneficiaries ARCHIVES OF INTERNAL MEDICINE Shreibati, J. B., Baker, L. C., Hlatky, M. A., Mell, M. W. 2012; 172 (19): 1456-1462

    Abstract

    Since January 1, 2007, Medicare has covered abdominal aortic aneurysm (AAA) screening for new male enrollees with a history of smoking under the Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act. We examined the association between this program and abdominal ultrasonography for AAA screening, elective AAA repair, hospitalization for AAA rupture, and all-cause mortality.We used a 20% sample of traditional Medicare enrollees from 2004 to 2008 to identify 65-year-old men eligible for screening and 3 control groups not eligible for screening (70-year-old men, 76-year-old men, and 65-year-old women). We used logistic regression to examine the change in outcomes at 365 days for eligible vs ineligible beneficiaries before and after SAAAVE Act implementation, adjusting for comorbidities, state-level smoking prevalence, geographic variation, and time trends.Fewer than 3% of abdominal ultrasonography claims after 2007 were for SAAAVE-specific AAA screening. There was a significantly greater increase in abdominal ultrasonography use among SAAAVE-eligible beneficiaries (2.0 percentage points among 65-year-old men, from 7.6% in 2004 to 9.6% in 2008; 0.7 points [8.9% to 9.6%] among 70-year-old men; 0.7 points [10.8% to 11.5%] among 76-year-old men; and 0.9 points [7.5% to 8.4%] among 65-year-old women) (P < .001 for all comparisons with 65-year-old men). The SAAAVE Act was associated with increased use of abdominal ultrasonography in 65-year-old men compared with 70-year-old men (adjusted odds ratio [AOR], 1.15; 95% CI, 1.11-1.19) (P < .001), and this increased use remained even when SAAAVE-specific AAA screening was excluded (AOR, 1.12; 95% CI, 1.08-1.16) (P < .001). Implementation of the SAAAVE Act was not associated with changes in rates of AAA repair, AAA rupture, or all-cause mortality.The impact of the SAAAVE Act on AAA screening was modest and was based on abdominal ultrasonography use that it did not directly reimburse. The SAAAVE Act had no discernable effect on AAA rupture or all-cause morality.

    View details for DOI 10.1001/archinternmed.2012.4268

    View details for Web of Science ID 000310070200005

    View details for PubMedID 22987204

  • Factors impacting follow-up care after placement of temporary inferior vena cava filters JOURNAL OF VASCULAR SURGERY Gyang, E., Zayed, M., Harris, E. J., Lee, J. T., Dalman, R. L., Mell, M. W. 2013; 58 (2): 440-445

    Abstract

    OBJECTIVE: Rates of inferior vena cava (IVC) filter retrieval have remained suboptimal, in part because of poor follow-up. The goal of our study was to determine demographic and clinical factors predictive of IVC filter follow-up care in a university hospital setting. METHODS: We reviewed 250 consecutive patients who received an IVC filter placement with the intention of subsequent retrieval between March 2009 and October 2010. Patient demographics, clinical factors, and physician specialty were evaluated. Multivariate logistic regression analysis was performed to identify variables predicting follow-up care. RESULTS: In our cohort, 60.7% of patients received follow-up care; of those, 93% had IVC filter retrieval. Major indications for IVC filter placement were prophylaxis for high risk surgery (53%) and venous thromboembolic event with contraindication and/or failure of anticoagulation (39%). Follow-up care was less likely for patients discharged to acute rehabilitation or skilled nursing facilities (P < .0001), those with central nervous system pathology (eg, cerebral hemorrhage or spinal fracture; P < .0001), and for those who did not receive an IVC filter placement by a vascular surgeon (P < .0001). In a multivariate analysis, discharge home (odds ratio [OR], 4.0; 95% confidence interval [CI], 1.99-8.2; P < .0001), central nervous system pathology (OR, 0.46; 95% CI, 0.22-0.95; P = .04), and IVC filter placement by the vascular surgery service (OR, 4.7; 95% CI, 2.3-9.6; P < .0001) remained independent predictors of follow-up care. Trauma status and distance of residence did not significantly impact likelihood of patient follow-up. CONCLUSIONS: Service-dependent practice paradigms play a critical role in patient follow-up and IVC filter retrieval rates. Nevertheless, specific patient populations are more prone to having poorer rates of follow-up. Such trends should be factored into institutional quality control goals and patient-centered care.

    View details for DOI 10.1016/j.jvs.2012.12.085

    View details for Web of Science ID 000322759500029

    View details for PubMedID 23588109

  • Late diagnosis of abdominal aortic aneurysms substantiates underutilization of abdominal aortic aneurysm screening for Medicare beneficiaries. Journal of vascular surgery Mell, M. W., Hlatky, M. A., Shreibati, J. B., Dalman, R. L., Baker, L. C. 2013; 57 (6): 1519-1523 e1

    Abstract

    Abdominal aortic aneurysm (AAA) screening remains largely underutilized in the U.S., and it is likely that the proportion of patients with aneurysms requiring prompt treatment is much higher compared with well-screened populations. The goals of this study were to determine the proportion of AAAs that required prompt repair after diagnostic abdominal imaging for U.S. Medicare beneficiaries and to identify patient and hospital factors contributing to early vs late diagnosis of AAA.Data were extracted from Medicare claims records for patients at least 65 years old with complete coverage for 2 years who underwent intact AAA repair from 2006 to 2009. Preoperative ultrasound and computed tomography was tabulated from 2002 to repair. We defined early diagnosis of AAA as a patient with a time interval of greater than 6 months between the first imaging examination and the index procedure, and late diagnosis as patients who underwent the index procedure within 6 months of the first imaging examination.Of 17,626 patients who underwent AAA repair, 14,948 met inclusion criteria. Mean age was 77.5 ± 6.1 years. Early diagnosis was identified for 60.6% of patients receiving AAA repair, whereas 39.4% were repaired after a late diagnosis. Early diagnosis rates increased from 2006 to 2009 (59.8% to 63.4%; P < .0001) and were more common for intact repair compared with repair after rupture (62.9% vs 35.1%; P < .0001) and for women compared with men (66.3% vs 59.0%; P < .0001). On multivariate analysis, repair of intact vs ruptured AAAs (odds ratio, 3.1; 95% confidence interval, 2.7-3.6) and female sex (odds ratio, 1.4; 95% confidence interval, 1.3-1.5) remained the strongest predictors of surveillance. Although intact repairs were more likely to be diagnosed early, over one-third of patients undergoing repair for ruptured AAAs received diagnostic abdominal imaging greater than 6 months prior to surgery.Despite advances in screening practices, significant missed opportunities remain in the U.S. Medicare population for improving AAA care. It remains common for AAAs to be diagnosed when they are already at risk for rupture. In addition, a significant proportion of patients with early imaging rupture prior to repair. Our findings suggest that improved mechanisms for observational management are needed to ensure optimal preoperative care for patients with AAAs.

    View details for DOI 10.1016/j.jvs.2012.12.034

    View details for PubMedID 23414696

  • Differences in readmissions after open repair versus endovascular aneurysm repair JOURNAL OF VASCULAR SURGERY Casey, K., Hernandez-Boussard, T., Mell, M. W., Lee, J. T. 2013; 57 (1): 89-95

    Abstract

    Reintervention rates after repair of abdominal aortic aneurysm (AAA) are higher for endovascular repair (EVAR) than for open repair, mostly due to treatment for endoleaks, whereas open surgical operations for bowel obstruction and abdominal hernias are higher after open repair. However, readmission rates after EVAR or open repair for nonoperative conditions and complications that do not require an intervention are not well documented. We sought to determine reasons for all-cause readmissions within the first year after open repair and EVAR.Patients who underwent elective AAA repair in California during a 6-year period were identified from the Health Care and Utilization Project State Inpatient Database. All patients who had a readmission in California ?1 year of their index procedure were included for evaluation. Readmission rates and primary and secondary diagnoses associated with each readmission were analyzed and recorded.From 2003 to 2008, there were 15,736 operations for elective AAA repair, comprising 9356 EVARs (60%) and 6380 open repairs (40%). At 1 year postoperatively, the readmission rate was 52.1% after open repair and 55.4% after EVAR (P=.0003). The three most common principle diagnoses associated with readmission after any type of AAA repair were failure to thrive, cardiac issues, and infection. When stratified by repair type, patients who underwent open repair were more likely to be readmitted with primary diagnoses associated with failure to thrive, cardiac complications, and infection compared with EVAR (all P<.001). Those who underwent EVAR were more likely, however, to be readmitted with primary diagnoses of device-related complications (P=.05), cardiac complications, and infection.Total readmission rates within 1 year after elective AAA repair are greater after EVAR than after open repair. Reasons for readmission vary between the two cohorts but are related to the magnitude of open surgery after open repair, device issues after EVAR, and the usual cardiac and infectious complications after either intervention. Systems-based analysis of these causes of readmission can potentially improve patient expectations and care after elective aneurysm repair.

    View details for DOI 10.1016/j.jvs.2012.07.005

    View details for Web of Science ID 000312833800016

    View details for PubMedID 23164606

  • Causes and Implications of Readmission After Abdominal Aortic Aneurysm Repair ANNALS OF SURGERY Greenblatt, D. Y., Greenberg, C. C., Kind, A. J., Havlena, J. A., Mell, M. W., Nelson, M. T., Smith, M. A., Kent, K. C. 2012; 256 (4): 595-605

    Abstract

    To determine the frequency, causes, predictors, and consequences of 30-day readmission after abdominal aortic aneurysm (AAA) repair.Centers for Medicare & Medicaid Services (CMS) will soon reduce total Medicare reimbursements for hospitals with higher-than-predicted 30-day readmission rates after vascular surgical procedures, including AAA repair. However, causes and factors leading to readmission in this population have never before been systematically analyzed.We analyzed elective AAA repairs over a 2-year period from the CMS Chronic Conditions Warehouse, a 5% national sample of Medicare beneficiaries.A total of 2481 patients underwent AAA repair--1502 endovascular aneurysm repair (EVAR) and 979 open aneurysm repair. Thirty-day readmission rates were equivalent for EVAR (13.3%) and open repair (12.8%). Although wound complication was the most common reason for readmission after both procedures, the relative frequency of other causes differed-eg, bowel obstruction was common after open repair, and graft complication after EVAR. In multivariate analyses, preoperative comorbidities had a modest effect on readmission; however, postoperative factors, including serious complications leading to prolonged length of stay and discharge destination other than home, had a profound influence on the probability of readmission. The 1-year mortality in readmitted patients was 23.4% versus 4.5% in those not readmitted (P < 0.001).Early readmission is common after AAA repair. Adjusting for comorbidities, postoperative events predict readmission, suggesting that proactively preventing, detecting, and managing postoperative complications may provide an approach to decreasing readmissions, with the potential to reduce cost and possibly enhance long-term survival.

    View details for DOI 10.1097/SLA.0b013e31826b4bfe

    View details for Web of Science ID 000308917600009

    View details for PubMedID 22964736

  • Predictors of emergency department death for patients presenting with ruptured abdominal aortic aneurysms JOURNAL OF VASCULAR SURGERY Mell, M. W., Callcut, R. A., Bech, F., Delgado, M. K., Staudenmayer, K., Spain, D. A., Hernandez-Boussard, T. 2012; 56 (3): 651-655

    Abstract

    Ruptured abdominal aortic aneurysm (rAAA) is a critically time-sensitive condition with outcomes dependent on rapid diagnosis and definitive treatment. Emergency department (ED) death reflects the hemodynamic stability of the patient upon arrival and the ability to mobilize resources before hemodynamic stability is lost. The goals of this study were to determine the incidence and predictors of ED death for patients presenting to EDs with rAAAs.Data for patients presenting with International Classification of Disease, 9th Revision, Clinical Modification codes for rAAA from 2006 to 2008 were extracted from discharge data using the Nationwide Emergency Department Sample (NEDS), Healthcare Cost and Utilization Project, and Agency for Healthcare Research and Quality. The NEDS is the largest stratified weighted sample of US hospital-based ED visits with links to inpatient files. We compared those transferred to those admitted and treated. Sample weights were applied to produce nationally representative estimates. Patient and hospital factors associated with transfer were identified using multivariate logistic regression. These factors were then analyzed for a relationship with ED deaths.A total of 18,363 patients were evaluated for rAAAs. Of these, 7% (1201) died in the ED, 6% (1160) were admitted and died without a procedure, 42% (7731) were admitted and died after repair, and 41% (7479) were admitted, treated, and survived. Transfers accounted for 4% (793) of all ED visits for rAAAs. ED death was more likely for patients seen in nonmetropolitan hospitals (12.7%) vs metropolitan nonteaching (7.0%) or metropolitan teaching hospitals (4.5%; P < .0001). Compared with other regions, the West had a higher ED mortality rate (9.6% vs 5.1%-6.9%; P = .0038). On multivariate analysis, ED death was associated with hospital groups exhibiting both high and low transfer rates.ED death remains a significant cause for mortality for rAAAs and varies by hospital type, rural/urban location, and geographic region. Both delays in ED arrival and delays in providing definitive care may contribute to increased ED death rates, suggesting that improved regional systems of care may improve survival after rAAA.

    View details for DOI 10.1016/j.jvs.2012.02.025

    View details for Web of Science ID 000308085500010

    View details for PubMedID 22560234

  • Payer status is associated with the use of prophylactic inferior vena cava filter in high-risk trauma patients SURGERY Pickham, D. M., Callcut, R. A., Maggio, P. M., Mell, M. W., Spain, D. A., Bech, F., Staudenmayer, K. 2012; 152 (2): 232-237

    Abstract

    It is controversial whether patients at high risk for pulmonary embolism (PE) should receive prophylactic inferior vena cava filters (IVC) filters. This lack of clarity creates the potential for variability and disparities in care. We hypothesized there would be differential use of prophylactic IVC filters for patients at high risk for PE on the basis of insurance status.We performed a retrospective analysis using the National Trauma Databank (2002-2007). We included adult patients at high risk for PE (traumatic brain injury or spinal cord injury) and excluded patients with a diagnosis of deep venous thrombosis (DVT) or PE. Logistic regression was performed to control for confounders and a hierarchical mixed effects model was used to control for center.A prophylactic filter was placed in 3,331 (4.3%) patients in the study cohort. Patients without insurance had an IVC filter placed less often compared with those with any form of insurance (2.7% vs 4.9%, respectively). After adjusting for confounders, we found that patients without insurance were less likely to receive a prophylactic IVC filter, even when we controlled for center (OR 5.3, P < .001).When guidelines lack clarity, unconscious bias has the potential to create a system with different levels of care based on socioeconomic disparities.

    View details for DOI 10.1016/j.surg.2012.05.041

    View details for Web of Science ID 000307157500013

    View details for PubMedID 22828145

  • Low Frequency of Primary Lipid Screening Among Medicare Patients With Rheumatoid Arthritis ARTHRITIS AND RHEUMATISM Bartels, C. M., Kind, A. J., Everett, C., Mell, M., McBride, P., Smith, M. 2011; 63 (5): 1221-1230

    Abstract

    Although studies have demonstrated suboptimal preventive care in RA patients, performance of primary lipid screening (i.e., testing before cardiovascular disease [CVD], CVD risk equivalents, or hyperlipidemia is evident) has not been systematically examined. The purpose of this study was to examine associations between primary lipid screening and visits to primary care providers (PCPs) and rheumatologists among a national sample of older RA patients.This retrospective cohort study examined a 5% Medicare sample that included 3,298 RA patients without baseline CVD, diabetes mellitus, or hyperlipidemia, who were considered eligible for primary lipid screening during the years 2004-2006. The outcome was probability of lipid screening by the relative frequency of primary care and rheumatology visits, or seeing a PCP at least once each year.Primary lipid screening was performed in only 45% of RA patients. Overall, 65% of patients received both primary and rheumatology care, and 50% saw a rheumatologist as often as a PCP. Any primary care predicted more lipid screening than lone rheumatology care (26% [95% confidence interval (95% CI) 21-32]). As long as a PCP was involved, performance of lipid screening was similar regardless of the balance between primary and rheumatology visits (44-48% [95% CI 41-51]). Not seeing a PCP at least annually decreased screening by 22% (adjusted risk ratio 0.78 [95% CI 0.71-0.84]).Primary lipid screening was performed in fewer than half of eligible RA patients, highlighting a key target for CVD risk reduction efforts. Annual visits to a PCP improved lipid screening, although performance remained poor (51%). Half of RA patients saw their rheumatologist as often or more often than they saw a PCP, illustrating the need to study optimal partnerships between PCPs and rheumatologists for screening patients for CVD risks.

    View details for DOI 10.1002/art.30239

    View details for Web of Science ID 000290609800009

    View details for PubMedID 21305507

  • For-Profit Hospital Status and Rehospitalizations at Different Hospitals: An Analysis of Medicare Data ANNALS OF INTERNAL MEDICINE Kind, A. J., Bartels, C., Mell, M. W., Mullahy, J., Smith, M. 2010; 153 (11): 718-W242

    Abstract

    About one quarter of rehospitalized Medicare patients are admitted to hospitals different from their original hospital. The extent to which this practice is related to for-profit hospital status and affects payments and mortality is unknown.To describe and examine predictors of and payments for rehospitalization at a different hospital among Medicare patients rehospitalized within 30 days at for-profit and nonprofit or public hospitals.Cohort study of patients discharged and rehospitalized from January 2005 to November 2006.Medicare fee-for-service hospitals throughout the United States.A 5% random national sample of Medicare patients with acute care rehospitalizations within 30 days of discharge (n = 74,564).30-day rehospitalizations at different hospitals and total payments or mortality over the subsequent 30 days. Multivariate logistic and quantile regression models included index hospital for-profit status, discharge counts, geographic region, rural-urban commuting area, and teaching status; patient sociodemographic characteristics, disability status, and comorbid conditions; and a measure of risk adjustment.16 622 patients (22%) in the sample were rehospitalized at a different hospital. Factors associated with increased risk for rehospitalization at a different hospital included index hospitalization at a for-profit, major medical school-affiliated, or low-volume hospital and having a Medicare-defined disability. Compared with patients rehospitalized at the same hospital, patients rehospitalized at different hospitals had higher adjusted 30-day total payments (median additional cost, $1308 per patient; P < 0.001) but no statistically significant differences in 30-day mortality, regardless of index hospital for-profit status.The database lacked detailed clinical information about patients and did not include information about specific provider practice motivations or the role of patient choice in hospitalization venues.Rehospitalizations at different hospitals are common among Medicare patients, are more likely among those initially hospitalized at a for-profit hospital, and are related to increased overall payments without improved mortality.University of Wisconsin Hartford Center of Excellence in Geriatrics, National Institutes of Health.

    View details for DOI 10.1059/0003-4819-153-11-201012070-00005

    View details for Web of Science ID 000285003800004

    View details for PubMedID 21135295

  • Effect of early plasma transfusion on mortality in patients with ruptured abdominal aortic aneurysm SURGERY Mell, M. W., O'Neil, A. S., Callcut, R. A., Acher, C. W., Hoch, J. R., Tefera, G., Turnipseed, W. D. 2010; 148 (5): 955-962

    Abstract

    The ratio of red blood cell (PRBC) transfusion to plasma (FFP) transfusion (PRBC:FFP ratio) has been shown to impact survival in trauma patients with massive hemorrhage. The purpose of this study was to determine the effect of the PRBC:FFP ratio on mortality for patients with massive hemorrhage after ruptured abdominal aortic aneurysm (RAAA).A retrospective review was performed of patients undergoing emergent open RAAA repair from January 1987 to December 2007. Patients with massive hemorrhage (?10 units of blood products transfused prior to conclusion of the operation) were included. The effects of patient demographics, admission vital signs, laboratory values, peri-operative variables, amount of blood products transfused, and the PRBC:FFP ratio on 30-day mortality were analyzed by multivariate analysis.One hundred and twenty-eight of the 168 (76%) patients undergoing repair for RAAA received at least 10 units of blood products within the peri-operative period. Mean age was 73.1 ± 9.1 years, and 109 (85%) were men. Thirty-day mortality was 22.6% (29/128), including 11 intra-operative deaths. By multivariate analysis, 30-day mortality was markedly lower (15% vs 39%; P < .03) for patients transfused at a PRBC:FFP ratio ?2:1 (HIGH FFP group) compared with those transfused at a ratio of >2:1 (LOW FFP), and the likelihood of death was more than 4-fold greater in the LOW FFP group (odds ratio 4.23; 95% confidence interval, 1.2-14.49). Patients in the HIGH FFP group had a significantly lower incidence of colon ischemia than those in the LOW FFP group (22.4% vs 41.1%; P = .004).For RAAA patients requiring massive transfusion, more equivalent transfusion of PRBC to FFP (HIGH FFP) was independently associated with lower 30-day mortality. The lower incidence of colonic ischemia in the HIGH FFP group may suggest an additional benefit of early plasma transfusion that could translate into further mortality reduction. Analysis from this study suggests the potential feasibility for a more standardized protocol of initial resuscitation for these patients, and prospective studies are warranted to determine the optimum PRBC:FFP ratio in RAAA patients.

    View details for DOI 10.1016/j.surg.2010.02.002

    View details for Web of Science ID 000283888000008

    View details for PubMedID 20378142

  • Presurgical Localization of the Artery of Adamkiewicz with Time-resolved 3.0-T MR Angiography RADIOLOGY Bley, T. A., Duffek, C. C., Francois, C. J., Schiebler, M. L., Acher, C. W., Mell, M., Grist, T. M., Reeder, S. B. 2010; 255 (3): 873-881

    Abstract

    To evaluate the use of time-resolved magnetic resonance (MR) angiography in the presurgical localization of the artery of Adamkiewicz prior to reimplantation of the feeding intercostal artery, lumbar artery, or both during aortic aneurysm repair.This institutional review board-approved retrospective study included 68 patients (36 men, 32 women) who underwent time-resolved spinal MR angiography (0.2 mmol per kilogram of body weight gadobenate dimeglumine administered at a rate of 2.0 mL per second) performed with a 3.0-T imager with a dedicated eight-element spine coil. Images were reviewed at a three-dimensional workstation by two experienced radiologists in consensus. The artery of Adamkiewicz was identified, and the location of the feeding intercostal and/or lumbar artery was ascertained by using a five-point confidence index (scores ranged from 1 to 5). The phases in which the artery of Adamkiewicz, aorta, and great anterior radiculomedullary vein (GARV) demonstrated peak enhancement were also recorded.The artery of Adamkiewicz and the location of the feeding intercostal and/or lumbar artery were identified with high confidence in 60 (88%) of the 68 patients. Origins of the artery of Adamkiewicz were on the left side of the body in 65% of patients and on the right side in 35%. The level of origin ranged from the T6 neuroforamina to the L1 neuroforamina. The arrival of contrast material was highly variable in this patient population, which had substantial aortic disease. The highest signal intensity in the aorta, artery of Adamkiewicz, and GARV occurred a mean of 55 seconds (range, 27-99 seconds; 95% confidence interval [CI] 51, 58), 72 seconds (range, 38-110 seconds; 95% CI: 68, 76), and 95 seconds (range, 46-156 seconds; 95% CI: 89, 101) after contrast material administration, respectively.The artery of Adamkiewicz and the anterior spinal artery can be identified and differentiated from the GARV even in patients with substantially altered hemodynamics by using time-resolved 3.0-T MR angiography.

    View details for DOI 10.1148/radiol.10091304

    View details for Web of Science ID 000278038500027

    View details for PubMedID 20501724

  • Impact of Intraoperative Arteriography on Limb Salvage for Traumatic Popliteal Artery Injury JOURNAL OF TRAUMA-INJURY INFECTION AND CRITICAL CARE Callcut, R. A., Acher, C. W., Hoch, J., Tefera, G., Turnipseed, W., Mell, M. W. 2009; 67 (2): 252-257

    Abstract

    Time to revascularization is speculated to be a major determinant of limb salvage for traumatic popliteal injuries. The purpose of this study was to determine whether location of diagnostic arteriography affected outcome.From 1996 to 2006, patients with popliteal injuries were identified from our trauma database. Additional data were extracted from chart review. Amputation rates for those undergoing arteriography performed in radiology (ARAD) versus the operating room (AOR) were compared.In 35 patients 36 limbs were treated, with 94% resulting from blunt mechanisms. The mean age was 37 years (11-69 years), 81% were men, and the mean Injury Severity Score was 15. The average mangled extremity severity scores (MESS) was 6 +/- 2. Follow-up was available in 97% patients with a median of 14 months. Overall amputation rate was 16.7% (6 of 36). Extremities with MESS <8 had 93% limb salvage, and MESS > or =8 had 55% limb salvage. ARAD (n = 10) and AOR (n = 15) groups were equivalent with regard to age, mechanism, Injury Severity Score, MESS, time to presentation, associated injuries, and fasciotomy rate. The median time from emergency room arrival to operating room was shorter (125 minutes vs. 214 minutes; p < 0.05) and salvage rate was higher (100% vs. 70%; p = 0.05) in the AOR group compared with the ARAD group.For popliteal artery injuries, diagnostic arteriography in the operating room reduces the likelihood of amputation by decreasing time to initiating repair and thereby limiting limb ischemia. Salvage is possible in the most severely injured extremities with rapid transport to the operating room.

    View details for DOI 10.1097/TA.0b013e31819ea796

    View details for Web of Science ID 000268898500008

    View details for PubMedID 19667876

  • A New Intercostal Artery Management Strategy for Thoracoabdominal Aortic Aneurysm Repair JOURNAL OF SURGICAL RESEARCH Mell, M. W., Wynn, M. M., Reeder, S. B., Tefera, G., Hoch, J. R., Acher, C. W. 2009; 154 (1): 99-104

    Abstract

    The purpose of this study is to describe a new approach for addressing the intraoperative management of intercostal arteries during thoracoabdominal aortic aneurysm (TAAA) repair, using preoperative spinal MRA for detection of intercostal arteries supplying the anterior spinal artery.Patients undergoing TAAA repair from August 2005 to September 2007 were included. Spinal artery MRA was performed to identify the anterior spinal artery, the artery of Adamkiewicz, and its major intercostal source artery (SA-AAK). Intraoperative spinal cord protection was carried out using standard techniques. Important intercostal arteries were either preserved or reimplanted as a button patch after removing aortic clamps. Demographic and perioperative data were collected for review. Analysis was performed with Fisher's exact test or Student's t-test, where applicable, using SAS ver. 8.0 (Cary, NC).Spinal artery MRA was performed in 27 patients. The SA-AAK was identified in 85% of preoperative studies. Open or endovascular repair was performed in 74% and 26% of patients, respectively. The SA-AAK was preserved or reimplanted in 13 (65%) of patients who underwent open repair. A mean of 1.67 (range 1-3) intercostal arteries were reimplanted. All patients undergoing endovascular repair necessitated coverage of the SA-AAK. No patient developed immediate or delayed paraplegia. Longer mean operative times in the reimplanted cohort were not statistically significant (330 versus 245 min, P = 0.1).The SA-AAK identified by MRA can be preserved or safely reimplanted after TAAA repair. Further study is warranted to determine if selective intercostal reimplantation can reduce the risk of immediate or delayed paraplegia.

    View details for DOI 10.1016/j.jss.2008.05.024

    View details for Web of Science ID 000266080000015

    View details for PubMedID 19101698

  • Adult-Onset Dysphagia Lusoria from an Uncommon Vascular Ring: A Case Report and Review of the Literature VASCULAR AND ENDOVASCULAR SURGERY Sitzman, T. J., Mell, M. W., Acher, C. W. 2009; 43 (1): 100-102

    Abstract

    Vascular rings are a rare cause of symptoms in adult patients. We report the case of a 48-year-old woman presenting with dysphagia lusoria due to an uncommon vascular ring: right aortic arch with mirror-image branching and a left ligamentum arteriosum. No previous reports exist of adult-onset dysphagia lusoria attributable to this anatomy. The patient underwent a limited muscle-sparing thoracotomy with division of the ligamentum. The division interrupted the vascular ring and relieved her esophageal compression. The presentation, evaluation, pathophysiology, and treatment of this condition are discussed.

    View details for DOI 10.1177/1538574408323503

    View details for Web of Science ID 000263636400014

    View details for PubMedID 18829585

  • Complications of spinal fluid drainage in thoracoabdominal aortic aneurysm repair: A report of 486 patients treated from 1987 to 2008 JOURNAL OF VASCULAR SURGERY Wynn, M. M., Mell, M. W., Tefera, G., Hoch, J. R., Acher, C. W. 2009; 49 (1): 29-35

    Abstract

    Spinal fluid drainage reduces paraplegia risk in thoracic (TAA) and thoracoabdominal (TAAA) aortic aneurysm repair. There has not been a comprehensive study of the risks of spinal fluid drainage and how these risks can be reduced. Here we report complications of spinal fluid drainage in patients undergoing TAA/TAAA repair.The study comprised 648 patients who had TAA or TAAA repair from 1987 to 2008. Spinal drains were used in 486 patients. Spinal fluid pressure was measured continuously, except when draining fluid, and was reduced to <6 mm Hg during thoracic aortic occlusion and reperfusion. After surgery, spinal fluid pressure was kept <10 mm Hg until patients were awake with normal leg lift. Drains were removed 48 hours after surgery. Spinal and head computed tomography (CT) scans were performed in patients with bloody spinal fluid or neurologic deficit. We studied the incidence of headache treated with epidural blood patch, infection, bloody spinal fluid, intracranial and spinal bleeding on CT, as well as the clinical consequences.Twenty-four patients (5%) had bloody spinal fluid. CT exams showed seven had no evidence of intracranial hemorrhage, 14 (2.9%) had intracranial blood without neurologic deficit, and three with intracranial bleeding and cerebral atrophy had neurologic deficits (1 died, 1 had permanent hemiparesis, and 1 with transient ataxia recovered fully). Two patients without bloody spinal fluid or neurologic deficit after surgery presented with neurologic deficits 5 days postoperatively and died from acute on chronic subdural hematoma. Neurologic deficits occurred after spinal fluid drainage in 5 of 482 patients (1%), and 3 died. The mortality from spinal fluid drainage complications was 0.6% (3 of 482). By univariate and multivariate analysis, larger volume of spinal fluid drainage (mean, 178 mL vs 124 mL, P < .0001) and higher central venous pressure before thoracic aortic occlusion (mean, 16 mm Hg vs 13 mm Hg, P < .0012) correlated with bloody spinal fluid.Strategies that reduce the volume of spinal fluid drainage but still control spinal fluid pressure are helpful in reducing serious complications. Patients with cerebral atrophy are at increased risk for complications of spinal fluid drainage.

    View details for DOI 10.1016/j.jvs.2008.07.076

    View details for Web of Science ID 000262547800006

    View details for PubMedID 18951749

  • Outcomes after endarterectomy for chronic mesenteric ischemia JOURNAL OF VASCULAR SURGERY Mell, M. W., Acher, C. W., Hoch, J. R., Tefera, G., Turnipseed, W. D. 2008; 48 (5): 1132-1138

    Abstract

    A retrospective study was performed to identify optimal factors affecting outcomes after open revascularization for chronic mesenteric ischemia.All patients who underwent open surgery for chronic mesenteric ischemia from 1987 to 2006 were reviewed. Patients with acute mesenteric ischemia or median arcuate ligament syndrome were excluded. Mortality, recurrent stenosis, and symptomatic recurrence were analyzed using logistic regression, and univariate and multivariate analysis.We identified 80 patients (69% women, 31% men). Mean age was 64 years (range, 31-86 years). Acute-on-chronic symptoms were present in 26%. Presenting symptoms included postprandial pain (91%), weight loss (69%), and food fear and diarrhea (25%). Preoperative imaging demonstrated severe (>70%) stenosis of the superior mesenteric artery in 75 patients (24 occluded), the celiac axis in 63 (20 occluded), and the inferior mesenteric artery in 53 (20 occluded). Multivessel disease was present in 72 patients (90%), and 40 (50%) underwent multivessel reconstruction. Revascularization was achieved by endarterectomy in 37 patients, mesenteric bypass in 29, and combined procedures in 14. Concurrent aortic reconstruction was required in 13 patients (16%). Three hospital deaths occurred (3.8%). Mean follow-up was 3.8 years (range, 0-17.2 years). One- and 5-year survival was 92.2% and 64.5%. Mortality was associated with age (P = .019) and renal insufficiency (P = .007), but not by clinical presentation. Symptom-free survival was 89.7% and 82.1% at 1 and 5 years, respectively. Symptoms requiring reintervention occurred in nine patients (11%) at a mean of 29 months (range, 5-127 months). Multivariate analysis showed that freedom from recurrent symptoms correlated with endarterectomy for revascularization (5.2% vs 27.6%; hazard ratio, 0.20; 95% confidence interval, 0.04-0.92; P = .02).For open surgical candidates, endarterectomy appears to provide the most durable long-term symptom relief in patients with chronic mesenteric ischemia.

    View details for DOI 10.1016/j.jvs.2008.06.033

    View details for Web of Science ID 000260725300010

    View details for PubMedID 18771889

  • A Quantitative Assessment of the Impact of Intercostal Artery Reimplantation on Paralysis Risk in Thoracoabdominal Aortic Aneurysm Repair ANNALS OF SURGERY Acher, C. W., Wynn, M. M., Mell, M. W., Tefera, G., Hoch, J. R. 2008; 248 (4): 529-538

    Abstract

    We previously demonstrated an 80% reduction in paraplegia risk using hypothermia, naloxone, steroids, spinal fluid drainage, intercostal ligation, and optimizing hemodynamic parameters. This report demonstrates that intercostal revascularization for the last 3 years further reduced our paraplegia risk index by 75%.We evaluated 655 patients who had thoracic or thoracoabdominal aneurysm repair for factors that affected paraplegia risk including aneurysm extent, acuity, cardiac function, blood pressure mean arterial pressure, and spinal fluid drainage with naloxone (SFDN). Eighteen patients died during or shortly after surgery leaving 637 patients for analysis of paralysis. We evaluated the effect of intercostal reimplantation (IRP) using a highly accurate (r(2) > 0.88) paraplegia risk index we developed and published previously.Fifty-eight percent of patients were male with a mean age of 67. Thirty-three percent were acute with rupture, acute dissection, mycotic aortitis, and trauma. Eighty (12%) had dissections. Thirty-five patients had paraplegia or paraparesis (5.4%). Significant factors by univariate analysis (P < 0.05) were Crawford type 2, acuity, SFDN, cardiac index after unclamping, mean arterial pressure during crossclamping, and IRP. In multivariate modeling, aneurysm extent, SFDN, acuity, and IRP remained significant (P < 0.02). The paraplegia risk index declined from 0.20 to 0.05 (P < 0.03).The incidence of paralysis after TAAA repair decreased from 4.83% to 0.88% and paralysis risk index decreased from 0.26 to 0.05 when intercostal artery reimplantation was added to neuroprotective strategies that had already substantially reduced paralysis risk. These findings suggest that factors that affect collateral blood flow and metabolism account for approximately 80% of paraplegia risk and intercostal blood flow accounts for 20% of risk. This suggests a limit to paraplegia risk reduction in thoracoabdominal endograft patients. Early results in this emerging field support this prediction of high paraplegia risk with thoracoabdominal branched endografts with extensive aortic coverage.

    View details for DOI 10.1097/SLA.0b013e318187a792

    View details for Web of Science ID 000260483700006

    View details for PubMedID 18936565

  • Effectiveness of intensive medical therapy in type B aortic dissection: A single-center experience JOURNAL OF VASCULAR SURGERY Tefera, G., Acher, C. W., Hoch, J. R., Mell, M., Turnipseed, W. D. 2007; 45 (6): 1114-1118

    Abstract

    Although the mainstay of managing acute descending thoracic aortic dissection (ADTAD) remains medical, certain patients will require emergency surgery for complications of rupture or ischemia. This study evaluates factors that affect outcome and determines which patients previously treated surgically would have been eligible for endovascular repair.A single-institution retrospective study was conducted of patients who presented with clinical signs of ADTAD that was confirmed by magnetic resonance angiography (MRA) or computed tomography (CT). All patients were admitted to the intensive care unit (ICU) and medically managed to maintain systolic blood pressure<120 mm Hg and heart rate<70 beats/min. Two treatment groups were identified: group 1 received medical treatment only; group 2 received medical treatment plus emergency surgery. Patient demographic and clinical data were correlated with 30-day group mortality and morbidity and need for emergency surgery. The MRA and CT scan images of group 2 were retrospectively reviewed to determine if currently available endovascular treatment could have been done. The Fisher exact test was used to compare between the groups, and P<.05 was considered significant.Between 1991 and 2005, 83 patients (55 men) were treated for ADTAD. The mean age was 67 years (range, 38 to 85). Sixty-eight patients (82%) had hypertension, three (3.6%) had Marfan syndrome, and 51 (62%) were smokers. Twenty-five (32%) of the patients were receiving beta-blocker therapy before the onset of their symptoms. Back pain was the most common initial symptom (72.2%). Emergency surgery was required in 19 patients (23%): 12 for rupture or impending rupture, four for mesenteric ischemia, and three for lower extremity ischemia. The need for emergency surgery was significantly higher in smokers (P=.03), in patients>70 years old (P=.035), and in patients who were not receiving beta-blocker therapy before the onset of symptoms (P=.023). The combined overall morbidity rate was 33%, and the mortality rate was 9.6%. Morbidity in group 2 was 64% and significantly higher than the 23% in group 1 (P=.00227). The mortality rate was also higher in group 2 at 31.5% compared with group 1 at 1.6% (P=.0004). Factors affecting the overall mortality included age>70 years (P=.057), previous abdominal aortic aneurysm repair (P=.018), tobacco use (P=.039), and the presence of leg pain at initial presentation (P=.013). As determined from the review of radiologic data, 11 of 13 patients with scans available for review in group 2 could have been treated with currently available endovascular grafts.Intensive medical therapies are effective in preventing early mortality associated with ADTAD. Predictably, the need for emergency surgery carries a high morbidity and mortality rate. Most patients in this series requiring emergency surgery could have been candidates for endovascular therapy had it been available.

    View details for DOI 10.1016/j.jvs.2007.01.065

    View details for Web of Science ID 000246931500004

    View details for PubMedID 17543672

  • Clinical utility of time-resolvcd imaging of contrast kinetics (TRICK-S) magnetic resonance angiography for infrageniculate arterial occlusive disease JOURNAL OF VASCULAR SURGERY Mell, M., Tefera, G., Thornton, F., Siepman, D., Turnipseed, W. 2007; 45 (3): 543-548

    Abstract

    The diagnostic accuracy of magnetic resonance angiography (MRA) in the infrapopliteal arterial segment is not well defined. This study evaluated the clinical utility and diagnostic accuracy of time-resolved imaging of contrast kinetics (TRICKS) MRA compared with digital subtraction contrast angiography (DSA) in planning for percutaneous interventions of popliteal and infrapopliteal arterial occlusive disease.Patients who underwent percutaneous lower extremity interventions for popliteal or tibial occlusive disease were identified for this study. Preprocedural TRICKS MRA was performed with 1.5 Tesla (GE Healthcare, Waukesha, Wis) magnetic resonance imaging scanners with a flexible peripheral vascular coil, using the TRICKS technique with gadodiamide injection. DSA was performed using standard techniques in angiography suite with a 15-inch image intensifier. DSA was considered the gold standard. The MRA and DSA were then evaluated in a blinded fashion by a radiologist and a vascular surgeon. The popliteal artery and tibioperoneal trunk were evaluated separately, and the tibial arteries were divided into proximal, mid, and distal segments. Each segment was interpreted as normal (0% to 49% stenosis), stenotic (50% to 99% stenosis), or occluded (100%). Lesion morphology was classified according to the TransAtlantic Inter-Society Consensus (TASC). We calculated concordance between the imaging studies and the sensitivity and specificity of MRA. The clinical utility of MRA was also assessed in terms of identifying arterial access site as well as predicting technical success of the percutaneous treatment.Comparisons were done on 150 arterial segments in 30 limbs of 27 patients. When evaluated by TASC classification, TRICKS MRA correlated with DSA in 83% of the popliteal and in 88% of the infrapopliteal segments. MRA correctly identified significant disease of the popliteal artery with a sensitivity of 94% and a specificity of 92%, and of the tibial arteries with a sensitivity of 100% and specificity of 84%. When used to evaluate for stenosis vs occlusion, MRA interpretation agreed with DSA 90% of the time. Disagreement occurred in 15 arterial segments, most commonly in distal tibioperoneal arteries. MRA misdiagnosed occlusion for stenosis in 11 of 15 segments, and stenosis for occlusion in four of 15 segments. Arterial access was accurately planned based on preprocedural MRA findings in 29 of 30 patients. MRA predicted technical success 83% of the time. Five technical failures were due to inability to cross arterial occlusions, all accurately identified by MRA.TRICKS MRA is an accurate method of evaluating patients for popliteal and infrapopliteal arterial occlusive disease and can be used for planning percutaneous interventions.

    View details for DOI 10.1016/j.jvs.2006.11.045

    View details for Web of Science ID 000244547900021

    View details for PubMedID 17223303

  • Absence of buttock claudication following stent-graft coverage of the hypogastric artery without coil embolization in endovascular aneurysm repair JOURNAL OF ENDOVASCULAR THERAPY Mell, M., Tefera, G., Schwarze, M., Carr, S., Acher, C., Hoch, J., Turnipseed, W. 2006; 13 (3): 415-419

    Abstract

    To evaluate the safety and efficacy of stent-graft coverage of the hypogastric artery origin without coil embolization during endovascular treatment of aortoiliac or iliac aneurysms.A retrospective study was conducted of patients who underwent endovascular aneurysm repair with endograft coverage of the hypogastric artery between September 2001 and September 2005. Among the 88 patients who underwent EVAR during the study period, 21 patients (19 men; mean age 77+/-6 years, range 67-86) had unilateral hypogastric artery coverage without coil embolization. Aneurysmal arteries included 11 aortoiliac, 8 isolated common iliac arteries (CIA), and 2 isolated hypogastric arteries. Preoperative AAA size was a mean 57 mm (range 46-73), and mean CIA aneurysm diameter was 36 mm (range 17-50). All covered hypogastric arteries were patent prior to the procedure. The stent-grafts implanted were 10 Excluder, 10 AneuRx, and 1 Zenith. Clinical outcome focused on mortality and morbidity, including the occurrence and duration of new-onset buttock claudication, which was further correlated with superior gluteal and profunda femoris artery patency.Immediate seal was achieved in all patients. Mean follow-up was 16 months (range 1-54). No type I endoleaks developed from the aortic or external iliac artery, and no type II endoleaks were found from the origin of the hypogastric artery. New-onset buttock claudication occurred in 2 (9.5%) patients, but resolved in both within 4 months. No additional secondary procedures, aneurysm rupture, or aneurysm-related death occurred.Stent-graft coverage of the orifice of the hypogastric artery without coil embolization is a safe and effective adjunct during the treatment of aortoiliac or iliac aneurysm, with a low incidence of buttock claudication.

    View details for Web of Science ID 000238334300019

    View details for PubMedID 16784331

  • Desmoid tumor of the sternum presenting as an anterior mediastinal mass EUROPEAN JOURNAL OF CARDIO-THORACIC SURGERY Saw, E., Yu, G. S., Mell, M. 1997; 11 (2): 384-386

    Abstract

    A 20-year-old man with a large, asymptomatic mediastinal mass was found to have desmoid-type fibromatosis (DF) by needle biopsy. The tumor arose from the internal periosteum of the sternum and mimicked an anterior mediastinal mass. A wide resection of the sternum, including portions of the clavicles and costal cartilages, and reconstruction with a Gore-Tex soft tissue patch were performed. Although extremely rare, desmoid tumor of the sternum should be considered in the differential diagnosis of anterior mediastinal tumors.

    View details for Web of Science ID A1997WM42300039

    View details for PubMedID 9080173

  • THE USE OF SPIRAL COMPUTED-TOMOGRAPHY IN THE EVALUATION OF LIVING DONORS FOR KIDNEY-TRANSPLANTATION TRANSPLANTATION Alfrey, E. J., Rubin, G. D., Kuo, P. C., WASKERWITZ, J. A., Scandling, J. D., MELL, M. W., Jeffrey, R. B., Dafoe, D. C. 1995; 59 (4): 643-645

    View details for Web of Science ID A1995QK22500037

    View details for PubMedID 7878773

  • SPIRAL COMPUTED-TOMOGRAPHY IN THE DIAGNOSIS OF TRANSPLANT RENAL-ARTERY STENOSIS TRANSPLANTATION MELL, M. W., Alfrey, E. J., Rubin, G. D., Scandling, J. D., Jeffrey, R. B., Dafoe, D. C. 1994; 57 (5): 746-748

    View details for Web of Science ID A1994NC19000019

    View details for PubMedID 8140637

  • The effect of antibiotics on the destruction of cartilage in experimental infectious arthritis. journal of bone and joint surgery. American volume Smith, R. L., Schurman, D. J., KAJIYAMA, G., Mell, M., Gilkerson, E. 1987; 69 (7): 1063-1068

    Abstract

    In joints with bacterial arthritis, continuing prolonged destruction of cartilage may occur in spite of prompt, effective antibiotic therapy. We measured the extent to which early antibiotic therapy with ceforanide altered the degradation of the cartilage after arthritis due to Staphylococcus aureus had been produced in the knee joint in rabbits. Degradation of the cartilage was quantified by analyses for glycosaminoglycan and collagen. Three weeks after the infection was produced, the cartilage had lost more than half of its glycosaminoglycan whether the antibiotic therapy had been started at one, two, or seven days after infection. Beginning the antibiotic treatment one day after infection reduced over-all loss of collagen by 37 per cent and decreased the area of erosion of the infected articular surfaces. When antibiotic treatment was begun at four, eight, or twelve hours after infection, the loss of glycosaminoglycan averaged 18 per cent. Prophylaxis with antibiotics completely prevented any degradation of the cartilage. Clinical relevance: The findings reported here show how rapidly cartilage loses glycosaminoglycan when it is involved by arthritis caused by staphylococci and how early treatment of the infection reduces the loss of collagen. There is less protection against loss of glycosaminoglycan. The results emphasize the need for early diagnosis and treatment of infectious synovitis and support the rationale for early administration of antibiotics without waiting for identification of the responsible bacteria.

    View details for PubMedID 3654698

Conference Proceedings


  • Long-term results after accessory renal artery coverage during endovascular aortic aneurysm repair Greenberg, J. I., Dorsey, C., Dalman, R. L., Lee, J. T., Harris, E. J., Hernandez-Boussard, T., Mell, M. W. MOSBY-ELSEVIER. 2012: 291-297

    Abstract

    Current information regarding coverage of accessory renal arteries (ARAs) during endovascular aneurysm repair (EVAR) is based on small case series with limited follow-up. This study evaluates the outcomes of ARA coverage in a large contemporary cohort.Consecutive EVAR data from January 2004 to August 2010 were collected in a prospective database at a University Hospital. Patient and aneurysm-related characteristics, imaging studies, and ARA coverage versus preservation were analyzed. Volumetric analysis of three-dimensional reconstruction computed tomography scans was used to assess renal infarction volume extent. Long-term renal function and overall technical success of aneurysm exclusion were compared.A cohort of 426 EVARs was identified. ARAs were present in 69 patients with a mean follow-up of 27 months (range, 1 to 60 months). Forty-five ARAs were covered in 40 patients; 29 patients had intentional ARA preservation. Patient and anatomic characteristics were similar between groups except that ARA coverage patients had shorter aneurysm necks (P = .03). Renal infarctions occurred in 84% of kidneys with covered ARAs. There was no significant deterioration in long-term glomerular filtration rate when compared with patients in the control group. No difference in the rate of endoleak, secondary procedures, or the requirement for antihypertensive medications was found.This study is the largest to date with the longest follow-up relating to ARA coverage. Contrary to previous reports, renal infarction after ARA coverage is common. Nevertheless, coverage is well tolerated based upon preservation of renal function without additional morbidity. These results support the long-term safety of ARA coverage for EVAR when necessary.

    View details for DOI 10.1016/j.jvs.2012.01.049

    View details for Web of Science ID 000307160400002

    View details for PubMedID 22480767

  • Predictors of surgical site infection after open lower extremity revascularization Greenblatt, D. Y., Rajamanickam, V., Mell, M. W. MOSBY-ELSEVIER. 2011: 433-439

    Abstract

    Surgical site infection (SSI) after open surgery for lower extremity revascularization is a serious complication that may lead to graft infection, prolonged hospitalization, and increased cost. Rates of SSI after revascularization vary widely, with most studies reported from single institutions. The objective of this study was to describe the rate and predictors of SSI after surgery for arterial occlusive disease using national data, and to identify any association between SSI and length of hospital stay, reoperation, graft loss, and mortality.Patients who underwent lower extremity arterial bypass or thromboendarterectomy from 2005-2008 were identified from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) participant use files. Multivariate logistic regression identified predictors of SSI. Odds ratios were adjusted for patient demographics, comorbidities, preoperative laboratory values, and operative factors. The association between SSI and other 30-day outcomes such as mortality and graft failure was determined.Of 12,330 patients who underwent revascularization, 1367 (11.1%) were diagnosed with an SSI within 30 days. Multivariate predictors of SSI included female gender (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.3-1.6), obesity (OR, 2.1; 95% CI, 1.8-2.4), chronic obstructive pulmonary disease (OR, 1.2; 95% CI, 1.0-1.5), dialysis (OR, 1.5; 95% CI, 1.1-2.1), preoperative hyponatremia (OR, 1.2; 95% CI, 1.0-1.4), and length of operation >4 hours (OR, 1.4; 95% CI, 1.2-1.6). SSI was associated with prolonged (>10 days) hospital stay (OR, 1.8; 95% CI, 1.4-2.1) and higher rates of 30-day graft loss (OR, 2.3; 95% CI, 1.7-3.1) and reoperation (OR, 3.7; 95% CI, 3.1-4.6). SSI was not associated with increased 30-day mortality.SSI is a common complication after open revascularization and is associated with a more than twofold increased risk of early graft loss and reoperation. Several patient and operation-related risk factors that predict postoperative SSI were identified, suggesting that targeted improvements in perioperative care may decrease complications and improve outcomes in this patient population.

    View details for DOI 10.1016/j.jvs.2011.01.034

    View details for Web of Science ID 000293814400026

    View details for PubMedID 21458203

  • Failure to rescue and mortality after reoperation for abdominal aortic aneurysm repair Mell, M. W., Kind, A., Bartels, C. M., Smith, M. A. MOSBY-ELSEVIER. 2011: 346-351

    Abstract

    Complications after abdominal aortic aneurysm (AAA) repair resulting in reintervention increase mortality risk, but have not been well studied. Mortality after reintervention is termed failure to rescue and may reflect differences related to quality management of the complication. This study describes the relationship between reoperation and mortality and examines the effect of physician speciality on reintervention rates and failure to rescue after AAA repair.Data were extracted for 2616 patients who underwent intact AAA repair in 2005 to 2006 from a standard 5% random sample of all Medicare beneficiaries. Patient demographics, comorbidities, hospital characteristics, repair type, and speciality of operating surgeon were collected. Primary outcomes were 30-day reoperation and 30-day mortality. Logistic regression analysis identified characteristics predicting reoperation.A total of 156 reoperations were required in 142 (4.2%) patients. Early mortality was far more likely for patients requiring reintervention than for those who did not (22.5% vs 1.5%; P < .0001). Of patients requiring reoperation, those requiring two or more interventions had an even higher mortality (54% vs 20%; P = .0007). Despite equivalent reoperation rates between specialities (vascular surgeons, 5.2%; others, 5.6%, P = .67), the mortality after reoperation was nearly half for vascular surgeons compared with other specialities (16.2% vs 32.3%; P = .04). The most common reason for reoperation was arterial complications (35.8%) accounting for the largest difference in mortality between vascular surgeons (30.7%) and other specialities (52.0%).Postoperative complications requiring reoperation dramatically increase mortality after AAA repair. Despite similar complication rates, vascular surgeons showed lower mortality rates after reoperation.

    View details for DOI 10.1016/j.jvs.2011.01.030

    View details for Web of Science ID 000293814400012

    View details for PubMedID 21498030

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